1. Technical Field
The techniques described herein relate generally to capacitive measurement and more specifically to touch and proximity detection using a touch screen having a capacitive sense matrix.
2. Discussion of the Related Art
A touch screen is a device that can detect an object in contact with a display area or in the proximity of the display area. The display area can be covered with a touch-sensitive matrix that can detect a user's touch by way of a finger or stylus, for example. Touch screens are used in various applications such as mobile phones and other mobile devices. A touch screen may enable various kinds of user input, such as touch selection of items on the screen or alphanumeric input via a displayed virtual keypad. Touch screens can measure various parameters of the user's touch, such as the location, duration, etc.
One type of touch screen is a capacitive touch screen. A capacitive touch screen may include a matrix of conductive lines and columns overlaid on the display area. The capacitance between each line and column of the matrix may be measured. A change in capacitance between a line and column can indicate that an object, such as a finger, is touching the screen near the region of intersection of the line and column.